The means are known on how to improve the anchorage capacity of metllic tubular piles by grouting, after driving, their walls to the terrain by means of cement grout. This grouting makes it possible to significantly increase the lateral friction of the pile with respect to the terrain and accordingly the resistance of the pile to compression effects, and especially traction effects. In order to do this, metallic tubular piles are already provided equipped with a device able to inject grout close to the wall of the tube forming the pile, this device being of the type comprising an injection pipe connected through a plurality of non-return valves to a plurality of injection orifices traversing the wall of the tube. In particular, one device described in the patent FR 2.237.475 contains non-return valves mounted in the actual wall of the tube of the pile, but without providing real protection.